inbreeding

American  

[in-bree-ding] / ˈɪnˌbri dɪŋ /

noun

Biology.

1. the mating of closely related individuals, as cousins, sire-daughter, brother-sister, or self-fertilized plants, which tends to increase the number of individuals that are homozygous for a trait and therefore increases the appearance of recessive traits.

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inbreeding Scientific  

/ ĭn′brē′dĭng /

1. The breeding or mating of related individuals within an isolated or closed group of organisms or people. Inbreeding can result in inbreeding depression. However, in agriculture and animal husbandry, the continued breeding of closely related individuals can help to preserve desirable traits in a stock.

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Etymology

Origin of inbreeding

First recorded in 1835–45; inbreed + -ing ¹

Example Sentences

Medieval goats displayed a broader range of genetic variation, while modern Old Irish Goats show clear signs of inbreeding.

From Science Daily • Feb. 26, 2026

In the meantime, populations are at risk of being wiped out by inbreeding, fierce wildfires or a number of other factors.

From Los Angeles Times • Feb. 12, 2026

"Our nature is very fragmented, due to railways and streets and cities. And this means we created a lot of barriers for the lynx, which leads to inbreeding," Dina says.

From BBC • May 1, 2025

In isolated populations like Sardinia’s, where inbreeding was common, such rare variants can become more frequent, a phenomenon called the founder effect.

From Science Magazine • Nov. 20, 2024

But selective inbreeding via marriage, Wells argued, might paradoxically produce weaker and duller generations.

From "The Gene" by Siddhartha Mukherjee